Bravo, Artemis team for an exceptional return to extra-orbital space travel.
What IIRC was actually done was that some antennas were placed on the back of the shuttle & its size was big enough that the plasma bubble would not fully envelope it - it would be open up to space. And that antenna on the back would communicate with TDRS satellites through this gap, enabling contact through the whole re-entry.
Starship does basically the same, just with Starlink satellites instead of TDRS.
https://en.wikipedia.org/wiki/Sprint_(missile)
"Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,000 km/h; 7,600 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,400 °C), requiring an ablative shield to dissipate the heat. The high temperature caused a plasma to form around the missile, requiring extremely powerful radio signals to reach it for guidance. The missile glowed bright white as it flew."
Also Orion and other capsules fall like a rock (steep reentry profile ) compared to shuttle/starship, which intentionally slow down the reentry and kinda glide (ballpark 10min with capsules compared to 30min with shuttle/starship).
tl;dr: capsules get fully enveloped in plasma due to their shape, size and reentry profile
The reason the heat shield failed was due to gas buildup inside the ablative material. This was due to the skip reentry profile they used, where the craft does a single skip (as in skipping stones) during reentry. The high bounce caused the shield to be heated enough that the heat penetrated the material causing gas release but not enough that the material ablated. Thus gas would build up deep inside up until it caused large chunks to break off. They could reproduce this in tests.
The fix was two-fold. First they lowered the bounce height, so a much less pronounced skip, avoiding the lowered heating of the shield. And they tweaked the material formula a bit so it was more porous, allowing subsurface gas to escape rather than build up.
I am very curious about what they're seeing, and how well the get-it-over-with solution worked.
It was a bold move and the results will be fascinating.
And from an older NASA explanation: https://www.nasa.gov/news-release/nasa-shares-orion-heat-shi...
> Engineers already are assembling and integrating the Orion spacecraft for Artemis III based on lessons learned from Artemis I and implementing enhancements to how heat shields for crewed returns from lunar landing missions are manufactured to achieve uniformity and consistent permeability.